Hello everyone, I am encountering a confusing performance issue in VR when using Niagara particles or materials with any level of transparency.
Even in an almost empty scene (just a single sphere), the framerate may suddenly drop to 2 FPS.
However, this behavior is completely inconsistent: sometimes the project runs perfectly and I can spawn many effects without any lag.
In some cases, it will stutter heavily for about 20–30 seconds and then magically return to full framerate, but other times it never recovers.
Opaque and unlit materials always behave fine, which is why I initially suspected translucent rendering, but I can’t confirm this with certainty.
This is happening on a powerful PC with the latest version of UE5 and standard VR settings such as Forward Rendering / MSAA / Instanced Stereo enabled.
Restarting the engine or reloading the level can completely change performance from one iteration to the next.
Has anyone experienced this type of unstable VR rendering behavior, and is there a known setting or workaround that might explain it?
Ok did some Stat GPU test, it appears that when I trigger my action that create a basic transparent sphere, the transparency goes to 55, and then it lags, and sometimes it goes back to 0 and never lag again
Also sometimes (like today) everytime I launch the game everything goes up to 600 (shadow projection etc etc) and it becomes unplayable, I have to restart unreal engine to make it back to normal
Unfortunetly I already have all my drivers up to date
Is this because Im using a transclucent shading on a sphere ? I need to test on a plane only, otherwise I’ll have to find solution to get a correct opacity, I mean, I cant even do a window glass ?
